Method of and apparatus for concentrating liquids



May 29, 1923.

l. HECHENBLEIKNER ET AL METHOD OF AND APPARATUS FOR CONCENTRATING LIQUIDS Filed June 26, 1922 mig Patented May 29, 1923..

UNirsD srrras y inseam PATENT carica.

INGENUIN HECHENBLEIKNER AND THOMAS C. OLIVER, OF CHARLOTTE, NORTH CAROLINA, ASSIGNORS TO CHEMICAL CONSTRUCTION COMPANY, OF NEW YORK, N. Y., A. CORPORATION F NORTH CAROLINA.

METHOD OF AND APPARATUS FOR CONCENTRATING. LIQUIDS.

Application led June 26, 1922. Serial No. 570,996.

To all whom. t may concern Be it known thatwe, INGENUIN HncHnN- nLElKNER and THOMAS C. OLIVER, citizens of the United States, and both residents of Charlotte, in the county of Mecklenburgand State of North Carolina, have invented certain new and useful Improvements in Methods of and Apparatus for Concentrating Liquids, of which the following is a l0 specification.

This invention relates to a method and apparatus for concentrating liquids such as sulphuric acid, and more particularly to a method and apparatus for concentratingT l5 sludge acids or separated sludge acids 0biained in the refining of petroleum oils; and has special reference to the provision of an improved concentrator of the type in which hot gases are blown or discharged through the acid for eecting a concentration thereof.

One of the known methods of concentratin sulphuric acid, as disclosed for example m our prior Patent No. 1,415,443

of May 9, 1922 and in our copending application Ser. No. 477,936, filed June 16, 1921, consists in blowing or bubbling hot air or gases through a body of the acid for. heating and agitating the same and effecting a concentration thereof below the true boiling point of the same. In this method the hot gases are conducted into a concentrating chamber and discharged into the body of acid therein below the surface thereof, the gases being injected and discharged into the acid through a plurality of submerged pipes provided with spaced perforations. In the practice of this method and the use of this apparatus, the heat exchange between the hot gases and the acid, and therefore in a large measure the eiiiciency of the concentrating step, depends upon the depth of submergence of the perforated pipes in the body of acid. It is apparent that` the deeper-the submergence the longer is the time element for a heat exchange between the acid and the hot gases issuing from the pipes; and in order to obtain a maximum heat exchange the pipes should be submerged a considerable depth below the level or surface of the acid in the compartment. This apparatus, however, where a maximum heat exchange is desired to be effected, has its limitations, since the depth of submergence of the perforated pipes can only be made relatively large at the expense of too great a consumption of power employed in placing the hot gases under that pressure suicient to drive the same through the deeply# submerged pipe sections and into the acid. In increasing the depth of submergence, a point is reached where the power consumed in driving the hot gases against the pressure and resistance of the acid is excessive and greater than the economy obtained in the heat exchange, and therefore the pipes, Where fuel economy is desired, cannot be submerged below a given depth. The perforated ipes are also relatively disadvantageous 'or the reason that resistance is met in the blowing of hot gases through the relatively small perforations therein, the perforations being moreover subject to liability of becoming plugged or stopped up by deposits in the concentrating chamber. To obviate these limitations and to remove the disadvantages inherent in and resulting from the employment of this method and apparatus are the principal objects of the present invention, the present invention comprehending an improved method and apparatus for concentrating the sul vphuric acid whereby a relatively long and therefore greater heat exchange is obtained between the hot gases and the acid at a relatively small depth of submergence, an eicient heat exchange and acid concentration being therefore obtained without that consumption of energy incident to the prior method.

A further principal object of the present l invention relates to a method ofintroducing the hot gases into the body of acid, whereby a circulatory motion is impar/ted to the acid while the hot gases are thoroughly comingled therewith, greater eiliciency being obtained in the concentrating step.

The principal objects of the .present invention may be said to include, besides the provision. of an improved concentrator having the characteristics and capable of producing the results above mentioned, the further provision of a method and apparatus for discharging or injecting hot gases into a body of acid below the level thereof in such a manner that the hot gases are constrained to move through the body of acid a substantial horizontal distance at a relatively small depth of submergence, whereby a heat exchange is effected over a relatively long path with a small energy consumption; the further provision of a method and apparatus of this nature in which one or more ducts or flues are provided in the concentratingchamber of the apparatus, the ducts or lues being so arranged therein as to lie below the normal acid level in the concentrating chamber, and in which the hot gases are introduced and injected into the said ducts or fines at one end thereof and caused to move through the said duct and through the acid filling the same substantially the full length of the ducts; and the still further provision of an apparatus of this nature in which the Aducts are open at both ends and the hot gases introduced' in such a manner as to effect a circulation of the acid through the said ducts while effecting an efficient comingling of the gases and the acid in the said ducts, concentration of the acid being obtained with great economy and efficiency.

To the accomplishment of the foregoing and such other objects aswill hereinafter appear, our invention consists in the elements and their relation one to the other, as hereinafter particularly described and sought to be defined in the claims, reference bein had to the accompanying drawings whic show a preferred embodiment of our invention and in which:

Fig. l is a cross-sectional elevational View of the apparatus of our present invention,

Fig. 2 is an enlarged fragmentary view thereof,

Fig. 3 is a cross-sectional view of the same on the line 3 3, Fig. 2, and

Fig. 4 is a fragmentary view incrosssection on the line lf-4, Fig. 1.

In the carrying out of our process for treating sludge acids or separated sludge acids, the acid is concentrated preferably inl two stages, the' acid being concentrated in the first stage up to an intermediate strength and thereafter treated in a second stage to effect completion of concentration thereof. In each stage of operation abody of acid is collected in a chamber and hot'gases such as hot air are introduced into the body of acid below the surface thereof, the heated gases effecting an agitation and heating of the acid body or bath, effectin a concentra-- tion thereof. The spent gases issue from the bath and move through a tower of checker work into which is fed the weak sludge acid, the said weak sludge acid running countercurrent to the spent gases moving up the tower, the weak feed acid being preheated in this manner and fed into the body of acid for concentration. The method, and apparatus of our present invention is intended to be used or employed in both stages of treatment for concentration of the acid, and for purposes of illustration onl one stage of concentration will be descri d, it being understood that the same process and apparatus ramera may be used for both stages or that the process and apparatus may be carried on merely in a single stage and may be used for the treatment of pure sulphuric acid as well as the sludge or separated sludge acid.

Referring to the drawings, the apparatus comprises a concentrating chamber C in which the body or bath of acid is concentrated, and a preheating tower T communicating with the concentrating chamber C, the spent gases issuing'- from the concentrating chamber having exit through the tower T, the said tower being employed for preheating a Weak sludge acid fed into the same from the top thereof as will become clearer hereinafter.

The concentrating chamber C vcomprises a trough-like` flue pro-vided with 'a bottom 10, side walls 11 and 12, andend walls 13 and 14 made of acid-proof brick laid in a suitable acid-proof mortar, a part of the said chamber being provided with an arched roof 15 also made of acid-proof material, the chamber being outwardly lined with lead, the lining forming a lead pan 16 covering the bottom, side and end walls of the chamber, the lead pan and concentrating for the spent gases moving up the tower and with an inlet (not shown) through which the weak acid or the weak sludge acid is admitted into the tower. The roof may also be provided with a closed manhole 21. The tower T is used for preheating purposes; and where a sludge acid is fed down the tower counter-current to the spent gases moving upwards therethrough, the temperalture of the tower is so regulated as to effect a preheatin'g of the weak sludge acid sulficient to drlve oli' the more volatile impurities therein. The tower T may also be provided at its bottom with a second manhole 22 for cleaning purposes.

For concentrating the acid iii-the chamber I C, means is provided' for conducting hot gases into and below the level of the acid, bath, the gases being discharged into thei acid for heating and agitating the same. As hereinbefore mentioned, the principal object of the present invention"comprehends the provision of a method and apparatus in which the hot gases are intrpduced into the bath so as to obtain a long a'nd eflicient heat exchange at a relatively small depth of submergence, and therefore with a relatively low energy consumption. To effect these results the hot gases are injected horizontally tions 30, the hot gases being into the acid bath and are caused to move a substantial horizontal distance at a relatively small depth of submergence, contact between the hot gases and the acid being obtained over a horizontal ath in contradistinction to a vertical pat as is the case in prior methods. To accomplish these ends one or more ducts or fines are arranged in the concentrating chamber C below the normal liquid level therein, so that the ducts or lues are normall lilled with the acid to be concentrated, an heated gases are injected into these fines by means of pipes communieating with the ilues and extending part way therein, the 'construction being such that the gases are constrained to move throughout the len h of the flues in contact with the acid filling the same. Referring now to the drawings, this construction includes the subdivision of the concentrating chamber C by means of the spaced vertical walls 23 and the arched roofs 24 into a-plurality of ducts or iiues 25, thesel liuc's being arran d below the normal liquid level 26 of t e acid so that the acid normally fills the same. Communicating with each of the lues 25 there is provided a gas conducting pipe formed preferably of a vertical pipe 'section 27 connected for communication to a manifold 28 supported on a suitable structure 29 and a horizontal pipe section 30 connected tothe vertical pipe section 27 by means of a packed joint 31 which may be of asbestos rope soaked in thick acid-proof cement, each pipe section- 30 extendin part way. and opening into a flue 25. he vertical pipe sections 27 are suitably sealed in the arched roof 15 of the concentrating chamber by means of a block 32 and ckin 33 of asbestos rope. The pipe sectlons 2 and 30 are of relatively large cross-sectional area, these pipes being for example about 10 inches in diameter. With this construction, the hot lgases are conducted from a source (not shown) through the manifold 28 and to and through the horizontally disposed pipe secinjected into the flues 25, the said gases being constrained by the said lues to move the full length thereof intimately intermixin with the acid therein. Tlie operation is suc that the acid is blown away by the hot gases from in front of the open pipe 30, and other acid immediately rushes in from the rear to take 'its place, a succession of bubbles and liquid being thereb developed, and acirculation of the acid t rou h the fiue in the direction of gas flow and a ve the flue in the reverse direction being thereb obtained, the flue open at both ends permitting an ecient aofitation and circulation of the acid. With this construction therefore, a low de th of submergence may be resorted to, w ile a relatively long path for the gases is provided, a greater heat exchange with a iven lerto'used. Another advantage of the brick flue construction is that the length of the flue can be materially shortened as compared with the perforated pipes in prior constructions, With the result that a smaller concentrating chamber may be employed, eiecting a reduction in first cost and a saving of plant space.

For supporting the pipe sections 27 and 30 in the concentrating chamber, there are provided a plurality of spaced piers 34 one for each of the vertical pipe sections, and a transversely arranged tie wall 35, the said tie Wall being provided with a plurality of ports 36, the latter being provided for permitting the circulation of the acid in and through the fines 25. -The horizontal pipe sections 30 are further supported in the llue by means of the oppositely positioned ipe supports 37 and 438. racing the arched roofs of the brick flues against being lifted by the force of the heated gases, spaced walls 39 are provided for bracing the roofs 24 of the flues a ainst the roof 15 ofthe concentratin cham er.

The concentrating chamber is provided ywith an. acid collecting compartment 40 in which the concentrated acid collects for removal, the saidcollecting compartment 40 communicating With the concentrating compartment of the chamber C by way of a plu- For suitably rality of spaced ports 41, the concentrated acid collecting in the compartment 40 feeding into onei or more'coolers 42 through the conducting piping 43.

For the purpose of cleaning the pipe sections 30 to remove any deposits accumulating therein and over the 'openings thereof, the wall 14 of the concentrating chamber is rovided with a plurality of cleaning open-f----'- ings 44, and each vertical pipe section 27 is provided with an orifice 45 arranged for registration with an opening 44, the construction being such that a suitable implement may be inserted through the opening 44 and orifice 45 and into the pipe section 30 for cleaning the same. i,

The manner of practicing the method and' using the apparatus will in the main beapparent from the above detailed descriptionthereof. The weak or dilute acid, such jected into Vthe acid below the surface thereof at a relatively small depth of submergence, the gases being injected into the ,f fines 25 for movement therethrough and in contact with the acid filling the same. The acid is thoroughly agitated by this treatment and a circulatory motion is imparted thereto, a heat exchange between the gases and the acid taking place over a considerable horizontal path. The gases when leaving the fines 25 still have a vertical distance to travel, a long heat exchange being thereby effected. The spent gases 1ssuing from the bath move 'up the preheating tower 'l and out through the exit iue 20. The concentrated acid collects in the compartment 40 and feeds into the coolers 42 for further concentration or further use.

lt will be apparent from the fore oing that we have provided an improve air blown concentrator in which the concentration of the acid may be eected in a very efficient and economical manner, the concentrator being rugged and strong in construction and al'ording an economy in first cost, in plant space, and in operation. lt will be further apparent that the method and apparatus may be used for concentrating other liquids, and Ythat the same may be used for edecting concentration ot pure as well as,` sludge acids, and that moreover the concentration may be eected in one or more stages. that numerous constructional changes may bc made without departing trom the spirit ot the invention defined in the following claims.

lille claim:

l. The method oi concentrating liquids which consists in injecting hot gases intov a body of the liquid below the level thereof and in constraining the said hot gases to move in Contact with the liquid over a substantial horizontal distance for edecting a heat exchange between the gases and the liquid over a relatively long path.

2. 'lhe method of concentrating sulphuric acid which consists in discharging hot gases into a body of the acid below the level thereof and in causing said gases to move in contact with the acid over a substantial horizontal distancefor e'ecting a heat exchange between the ases and the acid at a relatively small epth of submergence and over a relatively long path.

3. The method ot concentrating liquids which consists in lilling a relatively long duct with the li uid, in injectinghot gams into the duct and dischargin the se into the liquid lling the duct, witgh the hot gases lt will be further apparentV einen moving in contact with the liquid the length of the duct, whereby a heat exchange over a relatively long path and at a relatively small depth of submergence is ed'ected.

4. The method of concentrating liquids which consists in filling a horizontally arranged relatively lon duct in a concentrating chamber with tige liquid, in .injecting and discharging hot gases into the duct at one end thereof, and in constraining the hot gases to move throu h the duct and in contact with the liqui therein the length of the duc-t for effecting a heat exchange between the gases and the liquid over a relaivel long path for concentrating the iqul 5. 'lhe method of concentrating liquids which consists in' providing within a concentrating chamber a duct open at both ends and spaced from the top wall of the chamber, in filling the duct with the liquid, in injecting hot `gases into the duct at one end and causing the gases to move through the duct and in Contact with the liquid, whereby a. circulation of the liquid in and about the duct and a concentration of the saine is edected.

v, 6. The method of concentrating sulphuric acid which consists in providing a concentrating chamber having a plurality of extended horizontally arranged llues therein, in feeding a wealr` acid into the said chamber with the liquid level ot the acid maintained therein above the said lues whereby the lines are normally lilled with the acid, and in injecting and discharging hot gases into the llues and the acid tilling the same.

7. 'llhe method of concentrating liquids which consists in discharging hot gases into a body oit the liquid below the level thereof,` in constraining the said hot gases to move through the liquid a substantial distance in a horizontal direction for effecting a heat exchange between the gases and the liquid over a relatively long horizontal path at a relatively small depth oi" submergence.

8. An apparatus for concentrating liquids comprising a concentrating chamber adapted tor holding a body of the liquid and means tor discharging hot gases into the body ot the liquid below the level thereof and for constraining` the said hot gases to movein contact with the liquid over a substantial horizontal distance for edecting a heat exchange between the gases and the acid at a relatively small depth of submergence and over a relatively longl path.

9. An apparatus for concentrating sulphuric acid comprising a concentrating chamber adapted tor holding a body ot the acid, means for discharging hot gases into the body ot the acid below the level thereof., and means for causing the said gases to move in contact with the acid a substantial distance in a horizontal direction for edecting Cil 1,456,874 1 rfi a heat exchange between the gases and the liquid over a relatively long path and at a re atively small depth of submergence.

10. An vapparatus for concentrating sulphuric acid comprising' a concentratingr chamber adapted for holding a body of the acid, means for conducting hot gases into the body of the acid below the level thereof for discharge therein, means for causing the said hot gases to move in contact with the acid over a substantial horizontal distance, the said means being constructed and arranged to effect a circulation of the acid in the said chamber and a concentration there- 11. An apparatus for concentrating liquids comprising a concentrating chamber, a relatively long duct in said chamber arranged below the normal liquid level therein so that the liquid normally fills the same, and means for conducting and discharging hot' gases into said duct for horizontal movement through the liquid filling thesame for effecting a heat exchange between the gases and the liquid over a relatively long'path and at a relatively small depth of submergence. A

12. An apparatus for concentrating liquids comprising a` concentrating chamber, a relatively long duct in said chamberopen at both ends and arranged below the liquid level therein so that the liquid normally fills,

the said duct, and means for conducting `hot' gases intcsaid duct for horizontal movement through the liquid filling the same forl effecting a heat exchange between the gases and the liquid over a relatively long path and at a relatively small depth of submergence.

13. An apparatus for concentrating sulphuric acid comprising a concentrating chamber, a flue disposed horizontally therein, the said Hue being open at both ends and d being arranged in the said chamber below the normal acid level therein whereby the flue is normally lled with the acid, and means for injecting hot gases into the said ilue and horizontally through the said acid, whereby a circulation of the acid through and above the said flue and a heating and concentration thereof is effected.-v

14. An apparatus for concentrating liq.

uids comprisinga `concentrating chamber, a plurality of parallelly arranged flues in the said chamber, the said flues being each open at both ends and arranged below the normal liquid level in the chamber, and means for injecting hot gases into the iues at one end thereof for effecting a circulation of the liquid through and above the liues and a liquid level therein with the liquid normally filling the same, anda second duct smallerA than the said first duct and of relatively large cross-sectional area extending into the said first duct at one end thereof and opening into the same and arranged forconducting hot gases intothesaid duct and through the liquid lling the same.

17...An apparatus for concentrating liquids comprising a concentrating chamber, a plurality of parallelly disposed llues in the said chamber, the said flues being open at both ends, a pipe communicating witheach lflue and extending part' way into the same at one end, the said pipe being adapted for conducting and injecting hot gases into the llue for effecting a circulation and concentration of the liquid filling the same.

Signed by the said INGENUIN HEoHEN- BLEIKNER at Charlotte, in the county of Mecklenburg and State of North Carolina, this 14th day of June A. D. 1922.

INGENIN HEGHENBLEIKNER. Signed by the said THOMAS C. OLIVER at New York in the county of New York and State of New York, this 16th day of June,

. THOMAS C. OLIVER. 

